Linux errno详解

转自：https://www.cnblogs.com/Jimmy1988/p/7485133.html

 

1. 错误码 / errno

Linux中系统调用的错误都存储于 errno中，errno由操作系统维护，存储就近发生的错误，即下一次的错误码会覆盖掉上一次的错误。

PS: 只有当系统调用或者调用lib函数时出错，才会置位errno！

查看系统中所有的errno所代表的含义，可以采用如下的代码：

/* Function: obtain the errno string
*   char *strerror(int errno)
*/

#include <stdio.h>
#include <string.h>     //for strerror()
//#include <errno.h>
int main()
{
    int tmp = 0;
    for(tmp = 0; tmp <=256; tmp++)
    {
        printf("errno: %2d\t%s\n",tmp,strerror(tmp));
    }
    return 0;
}

输出信息如下：

errno:  0       Success
errno:  1       Operation not permitted
errno:  2       No such file or directory
errno:  3       No such process
errno:  4       Interrupted system call
errno:  5       Input/output error
errno:  6       No such device or address
errno:  7       Argument list too long
errno:  8       Exec format error
errno:  9       Bad file descriptor
errno: 10       No child processes
errno: 11       Resource temporarily unavailable
errno: 12       Cannot allocate memory
errno: 13       Permission denied
errno: 14       Bad address
errno: 15       Block device required
errno: 16       Device or resource busy
errno: 17       File exists
errno: 18       Invalid cross-device link
errno: 19       No such device
errno: 20       Not a directory
errno: 21       Is a directory
errno: 22       Invalid argument
errno: 23       Too many open files in system
errno: 24       Too many open files
errno: 25       Inappropriate ioctl for device
errno: 26       Text file busy
errno: 27       File too large
errno: 28       No space left on device
errno: 29       Illegal seek
errno: 30       Read-only file system
errno: 31       Too many links
errno: 32       Broken pipe
errno: 33       Numerical argument out of domain
errno: 34       Numerical result out of range
errno: 35       Resource deadlock avoided
errno: 36       File name too long
errno: 37       No locks available
errno: 38       Function not implemented
errno: 39       Directory not empty
errno: 40       Too many levels of symbolic links
errno: 41       Unknown error 41
errno: 42       No message of desired type
errno: 43       Identifier removed
errno: 44       Channel number out of range
errno: 45       Level 2 not synchronized
errno: 46       Level 3 halted
errno: 47       Level 3 reset
errno: 48       Link number out of range
errno: 49       Protocol driver not attached
errno: 50       No CSI structure available
errno: 51       Level 2 halted
errno: 52       Invalid exchange
errno: 53       Invalid request descriptor
errno: 54       Exchange full
errno: 55       No anode
errno: 56       Invalid request code
errno: 57       Invalid slot
errno: 58       Unknown error 58
errno: 59       Bad font file format
errno: 60       Device not a stream
errno: 61       No data available
errno: 62       Timer expired
errno: 63       Out of streams resources
errno: 64       Machine is not on the network
errno: 65       Package not installed
errno: 66       Object is remote
errno: 67       Link has been severed
errno: 68       Advertise error
errno: 69       Srmount error
errno: 70       Communication error on send
errno: 71       Protocol error
errno: 72       Multihop attempted
errno: 73       RFS specific error
errno: 74       Bad message
errno: 75       Value too large for defined data type
errno: 76       Name not unique on network
errno: 77       File descriptor in bad state
errno: 78       Remote address changed
errno: 79       Can not access a needed shared library
errno: 80       Accessing a corrupted shared library
errno: 81       .lib section in a.out corrupted
errno: 82       Attempting to link in too many shared libraries
errno: 83       Cannot exec a shared library directly
errno: 84       Invalid or incomplete multibyte or wide character
errno: 85       Interrupted system call should be restarted
errno: 86       Streams pipe error
errno: 87       Too many users
errno: 88       Socket operation on non-socket
errno: 89       Destination address 

转载于:https://www.cnblogs.com/x_wukong/p/10848069.html